Molecular oxygen can photogenerate four active states of oxygen including singlet oxygen, superoxide anion, hydrogen peroxide, and hydroxyl radical. Although these species have been shown to have damaging effects on proteins, research is particularly limited on their effects on eye tissues such as vitreous and lens. In the present study, dye-sensitized photooxidations of vitreous and lens components (hyaluronic acid and collagen, and lens crystallins, respectively) will be investigated by physicochemical methods such as absorptions, light scattering, fluorescence, circular dichroism, sedimentation velocity, and gel electrophoresis to correlate the effects of the various species of oxygen origin with the disorders of the eye.